[gdal-dev] warp taking time

[Chaitanya kumar CH]

Adiba,

Do you really need to warp the rasters? Aren't the source and destination
in the same SRS?


On Tue, Jul 15, 2014 at 9:25 AM, adiba nizami <adiba.nizami at gmail.com>
wrote:

> I am using gdal1.5 , considering version change not an option....can you
> please tell how I can make use of gdal warp ?...
>
>
>
> On Mon, Jul 14, 2014 at 1:22 PM, Chaitanya kumar CH <
> chaitanya.ch at gmail.com> wrote:
>
>> Adiba,
>>
>> I noticed that your source and target projections are same. Why not use
>> gdalbuildvrt and gdal_translate and skip the warping process? You create a
>> virtual mosaic (and assign the projection if needed) with buildvrt. You can
>> create a tiff file from the vrt file using gdal_translate.
>>
>>
>> On Mon, Jul 14, 2014 at 11:12 AM, adiba nizami <adiba.nizami at gmail.com>
>> wrote:
>>
>>> Sorry for the late reply. Here is the command i  gave :
>>>
>>> gdalwarp --config GDAL_CACHEMAX 512 -s_srs "+proj=aea +lat_1=28
>>> +lat_2=12 +lat_0=20 +lon_0=87 +x_0=2000000 +y_0=2000000 +ellps=WGS84
>>> +datum=WGS84 +units=m +no_defs" -t_srs "+proj=aea +lat_1=28 +lat_2=12
>>> +lat_0=20 +lon_0=87 +x_0=2000000 +y_0=2000000 +ellps=WGS84 +datum=WGS84
>>> +units=m +no_defs" -te -138559.10 571316.50 3010515.63 4012751.95 -tr 18 18
>>> -wm 512 -co "BIGTIFF=YES" -srcnodata 255 -dstnodata 255  file1.tif
>>> file2.tif ..... file28.tif output.tif
>>>
>>>
>>>
>>> On Thu, Jul 10, 2014 at 7:23 PM, Thornton, Michele M. <
>>> thorntonmm at ornl.gov> wrote:
>>>
>>>>  Hello,
>>>>
>>>>
>>>>
>>>> I’m interested in this thread.  One comment I can add about
>>>> gdal_merge.py is that it does not properly handle nodata values from the
>>>> full (padded) extent of the input files.  gdalwarp, which can be VERY slow,
>>>> does handle the nodata values correctly.
>>>>
>>>>
>>>>
>>>> Michele Thornton
>>>>
>>>>
>>>>
>>>> *From:* gdal-dev-bounces at lists.osgeo.org [mailto:
>>>> gdal-dev-bounces at lists.osgeo.org] *On Behalf Of *bas smit
>>>> *Sent:* Thursday, July 10, 2014 7:52 AM
>>>> *To:* Chaitanya kumar CH
>>>> *Cc:* gdal dev
>>>> *Subject:* Re: [gdal-dev] warp taking time
>>>>
>>>>
>>>>
>>>> I am wondering why you are using gdalwarp for mosaicing images having same
>>>> projection instead of gdal_merge.py?
>>>>
>>>>
>>>>
>>>> Bas Smit
>>>>
>>>>
>>>>
>>>> On Thu, Jul 10, 2014 at 7:14 PM, Chaitanya kumar CH <
>>>> chaitanya.ch at gmail.com> wrote:
>>>>
>>>> garfy,
>>>>
>>>>
>>>>
>>>> Please provide the gdalwarp command you used. Did you modify
>>>> GDAL_CACHEMAX?
>>>>
>>>>
>>>>
>>>> On Thu, Jul 10, 2014 at 3:26 PM, garfy <adiba.nizami at gmail.com> wrote:
>>>>
>>>> Dear All,
>>>>
>>>> I am trying to generate mosaic of 28 input images using *gdalwarp*.
>>>> All are in same projection. It has taken 5 days to generate the final
>>>> output.
>>>> Please find the gdalinfo of input and output attached. The input files
>>>> are
>>>> passed to warp in the order in which the gdalinfo is present in the
>>>> attachement.
>>>>
>>>> Any input on improving the time would be really helpful.
>>>>
>>>>
>>>> Thanks
>>>> input_files_gdalinfo.txt
>>>> <
>>>> http://osgeo-org.1560.x6.nabble.com/file/n5150453/input_files_gdalinfo.txt
>>>> >
>>>> final_output_gdalinfo.txt
>>>> <
>>>> http://osgeo-org.1560.x6.nabble.com/file/n5150453/final_output_gdalinfo.txt
>>>> >
>>>>
>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> View this message in context:
>>>> http://osgeo-org.1560.x6.nabble.com/warp-taking-time-tp5150453.html
>>>> Sent from the GDAL - Dev mailing list archive at Nabble.com.
>>>> _______________________________________________
>>>> gdal-dev mailing list
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>>>>
>>>>
>>>>
>>>>
>>>>
>>>> --
>>>> Best regards,
>>>> Chaitanya kumar CH.
>>>>
>>>> +91-9494447584
>>>> 17.2416N 80.1426E
>>>>
>>>>
>>>> _______________________________________________
>>>> gdal-dev mailing list
>>>> gdal-dev at lists.osgeo.org
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>>>>
>>>>
>>>>
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>>>>
>>>
>>>
>>>
>>> --
>>> Regards,
>>> Adiba Khan
>>>
>>
>>
>>
>> --
>> Best regards,
>> Chaitanya kumar CH.
>>
>> +91-9494447584
>> 17.2416N 80.1426E
>>
>
>
>
> --
> Regards,
> Adiba Khan
>



-- 
Best regards,
Chaitanya kumar CH.

+91-9494447584
17.2416N 80.1426E
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